Versioned Templated Dag Example

template.py

from datetime import datetime, timedelta
import os
from airflow.operators.bash_operator import BashOperator


DEFAULT_ARGS = { "retries": 0, catchup: False, max_active_runs: 1, schedule_interval: None }

def create_dag(env, version):

    dag_id = "hello_" + env

    dag = DAG(dag_id=dag_id, default_args=DEFAULT_ARGS)

    with dag:
        if version > "0.1.0":
            BashOperator(
                task_id="xsl_transform",
                bash_command='echo hello dave',
                dag=dag)
        else:
            BashOperator(
                task_id="xsl_transform",
                bash_command='echo hello world',
                dag=dag)

    return dag

template_dag.py

from template import create_dag
from airflow.models import Variable
from airflow import DAG # Required or airflow-webserver skips file.

"""
Using the template
This doesn't need to be a separate file.
"""

version = Variable.get("hello_qa_version")
dag = create_dag("qa", version)
globals()[dag.dag_id] = dag

version = Variable.get("hello_prod_version")
dag = create_dag("prod", version)
globals()[dag.dag_id] = dag